THE NERVOUS SYSTEM
Introduction:
The nervous system is the master communicating and controlling center of the body. Its three
main functions are to monitor changes outside the body using the sensory cells of the body, to
process the sensory input and determine the proper response, and to cause the response by
transmitting signals to the effector organs of the body.
I. HISTOLOGY: Use the microscope and prepared slides to study the structures listed.
A. Using the slides labeled "Motor Neuron", learn to recognize the following:
1. neuroglia cells
2. multipolar neuron Picture
a. cell body (soma)
b. nucleus (and nucleolus)
c. nerve cell processes (axon and dendrites)
B. Study of the neuron model. Picture 1, Picture 2, Picture 3, Picture 4
1. dendrites
2. axon
3. nodes of Ranvier
4. cell body
5. nucleus
6. endoneurium
7. myelin sheath
8. nissl bodies
9. schwann cell with nucleus
C. Identify the following structures on the model and the slide labeled "Spinal Cord" crosssection (c.s.) Picture 1 and Picture 2
1. central canal
2. anterior median fissure
3. posterior median sulcus
4. anterior and posterior horns of gray
5. dorsal root ganglia (if attached)
6. gray matter containing cell bodies of neurons
7. white matter containing cross-sections of myelinated fibers
D. Using the slide labeled "Peripheral Nerve, c.s", learn to recognize the following:
Picture 1and Picture 2
1. epineurium, perineurium, fascicles, and endoneurium
2. cross-section of myelinated axon
II. GROSS ANATOMY: Use available sketches, photographs, and written descriptions in your
textbook and lab atlas to help you with the following tasks.
A. Study the life-sized spinal cord model and learn to recognize the following structures:
Picture 1and Picture 2
1. Brain stem structures
a. pons
b. medulla oblongata
2. Other brain structures visible
a. Optic nerve and optic chiamsa
b. Frontal lobe and olfactory nerve (and bulb)
3. Spinal cord in vertebral canal
a. conus medullaris
b. cauda equina
4. Spinal nerve roots, spinal nerves, plexuses, and peripheral nerves
a. cervical plexus
b. brachial plexus
c. intercostal nerves
d. lumbar plexus
e. sacral plexus
f. sciatic nerve
5. Sympathetic trunk with sympathetic chain ganglia
C. Study the model of the brain ventricles. Picture 1, Picture 2 and Picture 3
1. lateral ventricles (right and left)
2. third ventricle (with interventricular foramen/foramen of Monro)
3. cerebral aqueduct
4. fourth ventricle
5. choroid plexus
D. Study the models of the entire brain.
1. cerebral hemisphere Picture 1, Picture 2, Picture 3, and Picture 4
a. Parietal lobe, frontal lobe, occipital lobe, and temporal lobe
b. optic chiasma
c. olfactory bulbs
d. central sulcus
e. precentral gyrus
f. postcentral gyrus
g. lateral sulcus
h. white and grey matter
2. longitudinal fissure and transverse fissure
3. Cerebellum
4. pons
5. medulla oblongata
6. all twelve cranial nerves
a. Olfactory Nerve (I)
b. Optic Nerve (II)
c. Oculomotor (III)
d. Trochlear (IV)
e. Trigeminal (V)
f. Abducens (VI)
g. Facial (VII)
h. Vestibulocochlear (VIII)
i. Glossopharyngeal (IX)
j. Vagus (X)
k. Accessory (XI)
l. Hypoglossal (XII)
7. pitutary gland
E. Study any sagittal section of plastic imbedded human brains. In addition to the above
structures, learn to recognize the following structures:
Picture 1, Picture 2
1. corpus callosum
2. septum pellucidum
3. thalamus
4. massa intermedia
5. anterior and posterior commisure
6. third and fourth ventricles
7. Midbrain
8. arbor vitae
9. hypothalamus
10. pituitary gland
11. pineal gland
12. pia mater
F. Study the preserved sheep brain. Find the following parts: Picture 1, Picture 2,
Picture 3, Picture 4, Picture 5, and Picture 6
1. meninges (dura and pia mater)
2. cerebrum and the various lobes
3. longitudinal fissure
4. transverse fissure
5. cerebellum
6. optic nerve and optic chiasma
7. olfactory bulb
8. spinal cord
9. corpus callosum (septum pellucidum if visible)
10. ventricles
11. cerebral aqueduct
12. pons
13. medulla oblongata
14. arbor vitae